In recent years, study has been made on optical recording media for recording or reading information using a laser beam, etc., in which storage capacity per disc can be increased by laminating recording layers into a multi-layered structure. See Patent Literatures 1-3 and Non-patent Literatures 1-3.
Meanwhile, study has also been made to realize a high-capacity cartridge, in which a large number of extremely-thin flexible discs (see, for example, Patent Literatures 4-6 and Non-patent Literature 4) are stored in a cartridge case and taken out and used one by one using a changer.